Supercritical fluid extraction, LC-MS profiling, and QbD-guided green HPLC method for standardization of Careya arborea Roxb. nanoemulsion

Careya arborea Roxb. was investigated for its phytotherapeutic potential, focusing on two key bioactive constituents, (−)-epigallocatechin-3-gallate (EGCG) and azelaic acid (AzA). These compounds were efficiently extracted using supercritical fluid extraction (SFE), a green and selective technique. The chemical composition of the extract was confirmed through liquid chromatography–mass spectrometry (LC-MS), verifying the presence of both EGCG and AzA. To improve bioavailability and dermal absorption, the extract was formulated into a nanosuspension using suitable stabilizers and homogenization techniques. A robust and reproducible reverse-phase high-performance liquid chromatography method was developed for the quantitative estimation of EGCG and AzA in both the crude extract and nanosuspension. Method development was guided by a quality by design approach using central composite design, optimizing key chromatographic parameters with minimal experimentation. EGCG was separated using a Chemsil ODS C18 column with methanol and 0.1% orthophosphoric acid (60:40 v/v) at 276 nm, while AzA was analyzed using a Phenomenex Luna C18 column with acetonitrile and 0.1% formic acid (80:20 v/v) at 227 nm. The method was validated as per ICH Q2(R1) guidelines, showing high accuracy, precision, and robustness. Green chemistry metrics such as Analytical Eco-Scale and Analytical GREEnness confirmed the method’s environmental sustainability.